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Vanguard
®
ID Total Knee
Surgical Technique
Tibial Resection
(cont.)
Trialing
Based on the tibial template size, select the appropriate
tibial trial and the appropriate medial and lateral
bearing based on the constraint level desired (see
bearing compatibility chart, page 24).
Free float the tibial trial and assembled trial bearing on
the prepared tibia (Figure 30).
Place the femoral trial onto the femur with the
dedicated femoral impactor.
With the trial components in place, check the range of
motion and stability of the knee.
Note:
Up to 2 mm difference in thickness between
the medial and lateral bearings may be used to
match the soft tissue envelope of the knee.
If range of motion and stability are appropriate, drill
holes for the distal femoral pegs through the trial
femoral component using the lug drill.
Determine final rotation of the tibia and mark the
position in the following way:
– Extend the anterior marks of the tibial trial onto
the anterior tibia with electrocautery
Figure 30
Vanguard ID Tip
:
When trialing range of motion,
if the medial and lateral bearings rise up in flexion:
a. Confirm the tibial tray is not undersized.
b. Confirm that the posterior slope is adequate.
If the medial trial bearing rises up during flexion:
a. Confirm there is not excessive external rotation
of the tibial tray.
b. Confirm that the tibial tray is not undersized
If the lateral trial bearing rises up during flexion:
a. Confirm that there is not excessive internal
rotation of the tibial tray.
b. Confirm that the tibial tray is not undersized.
Attention: Use only up to 2 mm difference in
bearing thickness between the medial and lateral
bearings. Utilizing bearings that differ in thickness
by more than 2 mm has not been evaluated and
could lead to premature failure of the device.
